[llvm] [Exegesis][RISCV] Add RISCV support for llvm-exegesis (PR #89047)

[via llvm-commits]

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@@ -0,0 +1,60 @@
+# RUN: llvm-exegesis -mode=latency -mtriple=riscv64-unknown-linux-gnu --benchmark-phase=assemble-measured-code -opcode-name=LD | FileCheck --check-prefix=TEST1 %s
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AnastasiyaChernikova wrote:

Changed prefix in FileCheck to opcode name, thanks. I prefer to leave RUN near the CHECK lines. It is more logical and easy to read for me

https://github.com/llvm/llvm-project/pull/89047